- All subjects must understand that lenalidomide could have a potential teratogenic risk, agree to abstain from donating blood with taking lenalidomide therapy and following discontinuation of study drug therapy; have an echocardiogram (ECG) or multigated acquisition (MUGA) scan of the heart demonstrating left ventricular ejection fraction (LVEF) at least 50% or the institution's lower limit of normal; have recovered from adverse, toxic effects of prior therapies to equal to or less than 1 (National Cancer Institute [NCI] Common Terminology Criteria for Adverse Events [CTCAE] version 4.03 except for alopecia and peripheral neuropathy.